﻿using System;
using System.Text;
using LibUsbDotNet;
using LibUsbDotNet.LibUsb;
using LibUsbDotNet.Main;

namespace Examples;

internal class ReadPolling
{
    public static IUsbDevice MyUsbDevice;

    #region SET YOUR USB Vendor and Product ID!

    public static UsbDeviceFinder MyUsbFinder = new()
    {
        Vid = 0x1234,
        Pid = 0x0000
    };

    #endregion

    public static void Main(string[] args)
    {
        Error ec = Error.Success;

        using (UsbContext context = new UsbContext())
        {
            try
            {
                // Find and open the usb device.
                MyUsbDevice = (UsbDevice)context.Find(MyUsbFinder);

                // If the device is open and ready
                if (MyUsbDevice == null) throw new Exception("Device Not Found.");

                // If this is a "whole" usb device (libusb-win32, linux libusb-1.0)
                // it exposes an IUsbDevice interface. If not (WinUSB) the 
                // 'wholeUsbDevice' variable will be null indicating this is 
                // an interface of a device; it does not require or support 
                // configuration and interface selection.
                IUsbDevice wholeUsbDevice = MyUsbDevice as IUsbDevice;
                if (!ReferenceEquals(wholeUsbDevice, null))
                {
                    // This is a "whole" USB device. Before it can be used, 
                    // the desired configuration and interface must be selected.

                    // Select config #1
                    wholeUsbDevice.SetConfiguration(1);

                    // Claim interface #0.
                    wholeUsbDevice.ClaimInterface(0);
                }

                // open read endpoint 1.
                var reader = MyUsbDevice.OpenEndpointReader(ReadEndpointID.Ep01);


                byte[] readBuffer = new byte[1024];
                while (ec == Error.Success)
                {
                    int bytesRead;

                    // If the device hasn't sent data in the last 5 seconds,
                    // a timeout error (ec = IoTimedOut) will occur. 
                    ec = reader.Read(readBuffer, 5000, out bytesRead);

                    if (bytesRead == 0) throw new Exception(string.Format("{0}:No more bytes!", ec));
                    Console.WriteLine("{0} bytes read", bytesRead);

                    // Write that output to the console.
                    Console.Write(Encoding.Default.GetString(readBuffer, 0, bytesRead));
                }

                Console.WriteLine("\r\nDone!\r\n");
            }
            catch (Exception ex)
            {
                Console.WriteLine();
                Console.WriteLine((ec != Error.Success ? ec + ":" : String.Empty) + ex.Message);
            }
            finally
            {
                if (MyUsbDevice != null)
                {
                    if (MyUsbDevice.IsOpen)
                    {
                        // If this is a "whole" usb device (libusb-win32, linux libusb-1.0)
                        // it exposes an IUsbDevice interface. If not (WinUSB) the 
                        // 'wholeUsbDevice' variable will be null indicating this is 
                        // an interface of a device; it does not require or support 
                        // configuration and interface selection.
                        IUsbDevice wholeUsbDevice = MyUsbDevice as IUsbDevice;
                        if (!ReferenceEquals(wholeUsbDevice, null))
                        {
                            // Release interface #0.
                            wholeUsbDevice.ReleaseInterface(0);
                        }

                        MyUsbDevice.Close();
                    }
                    MyUsbDevice = null;
                }

                // Wait for user input..
                Console.ReadKey();
            }
        }
    }
}